/**
 * This file is part of 1genia trampoline
 * Copyright (C) 2007-2008 1genia (contact@1genia.com)
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; version 3 of the License. 
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details. 
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; see the file COPYING.TXT.  If not,
 * write to the Free Software Foundation, Inc., 51 Franklin Street,
 * Fifth Floor, Boston, MA 02110-1301, USA. 
 **/
package com.genia.toolbox.projects.toolbox_basics_project.web.taglib;

import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.context.support.WebApplicationContextUtils;

import com.genia.toolbox.persistence.exception.PersistenceException;
import com.genia.toolbox.projects.toolbox_basics_project.bean.model.I18nDynamicValue;

/**
 * Jstl functions that delegate to a spring bean.
 */
public class Functions
{

  /**
   * the spring name of the bean containing the actual functions.
   */
  private static final String BEAN_NAME = "basicProjectWebSpringFunctions";



  /**
   * returns the spring bean containing the actual functions.
   * 
   * @return the spring bean containing the actual functions
   */
  private static SpringFunctions getSpringFunctions()
  {
    final RequestAttributes currentRequestAttributes = RequestContextHolder.currentRequestAttributes();
    if (currentRequestAttributes == null) {
      return null;
    }
    if (currentRequestAttributes instanceof ServletRequestAttributes) {
      return (SpringFunctions) WebApplicationContextUtils.getWebApplicationContext(((ServletRequestAttributes) currentRequestAttributes).getRequest().getSession().getServletContext()).getBean(
          BEAN_NAME);
    }
    return null;
  }



  /**
   * translate a {@link I18nDynamicValue} in the current language.
   * 
   * @param value
   *          the value to translate
   * @return the translated value
   * @throws PersistenceException
   *           when an error occured
   */
  public static String translate(I18nDynamicValue value)
      throws PersistenceException
  {
    return getSpringFunctions().translate(value);
  }



  /**
   * returns the current value of the parameter with the reference name given in
   * parameter.
   * 
   * @param parameterName
   *          the name of the parameter
   * @return the current value of the parameter with the reference name given in
   *         parameter
   */
  public static Object getParameter(String parameterName)
  {
    return getSpringFunctions().getParameter(parameterName);
  }
}
